A mockup of a disinfection gateway for use in inhibiting the spread of infections.

Would everyone have to go through disinfection at these airlocks? Visitors and patients entering a hospital for an appointment don’t present the same level of risk (though they might be tested for infection themselves). Unlike care providers who go from patient to patient to patient, they don’t act as agents for transmission. Accordingly, the same protocols need not apply. Similarly, a caregiver who is only interacting with a single patient need not undergo this process. Furthermore, these protocols could be overridden for the sake of speed in the event of an emergency—when protocols are generally observed, a single contact is unlikely to transmit pathogens.

The same principles of containment are behind biological membranes that prevent transmissions between parts of the body, and are the reason why the immune system is concentrated in the high-speed transport system of the body—the blood. It is the reason we have regulations about plant and animal products crossing national borders. Conversely, the absence of such boundary protections in an increasingly interconnected world has promoted the rise of highly virulent new strains of pathogens and the risks of global pandemics.

Reducing the probability of transmission at each provider-to-patient contact by hand washing and other protocols is still a good idea. At the same time, the flow of pathogens through a hospital and overall transmission between sites can be dramatically reduced. This can be done by creating additional levels of transmission-prevention at key internal boundaries in the care facility and between care facilities.

The cost of hospital-based infections is high and using high-leverage methods to eliminate them is the way to go. By instituting protocols at geographic domain boundaries, at low cost, we can dramatically reduce their transmission.